TDM850 flywheel used in a TRX850

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dazzer106
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TDM850 flywheel used in a TRX850

Post by dazzer106 » Tue Jun 25, 2019 10:27 am

Has anyone on the forum ever used a flywheel from a 96 TDM in a TRX 850. The yamaha part numbers are identical apart from the first 3 model numbers. A 96 rotor assembly is listed as 4NX-81450-00. The 96 TDM part is 4TX-81450-00.
I am restoring my 96 trx engine and during the engine being stripped, the rotor assembly (flywheel) rusted badly and I wanted to replace it. I bought a cheap TDM flywheel off E-bay and it looks identical to my old TRX unit apart from three small drillings on the TDM unit.
Thanks in advance for any advice given.

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Tarwetijger
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Re: TDM850 flywheel used in a TRX850

Post by Tarwetijger » Tue Jun 25, 2019 1:22 pm

Drillings are for balancing I suppose.
With both engines being 270 degree cranks, the flywheels should be interchangable. Although the different codes in partnumbers make me less sure about it. After a visual comparison if they are the same I would give it a try.

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jpe70
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Re: TDM850 flywheel used in a TRX850

Post by jpe70 » Tue Jun 25, 2019 9:24 pm

4NX simply says it's early TRX. Europeans are 4UN. 4TX is the name of 2nd gen TDM...

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Tarwetijger
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Re: TDM850 flywheel used in a TRX850

Post by Tarwetijger » Wed Jun 26, 2019 8:54 am

jpe70 wrote:4NX simply says it's early TRX. Europeans are 4UN. 4TX is the name of 2nd gen TDM...
I know, but the different partnumber might suggest it is specifically made for that model.
In the partlist of the TRX are also partnumbers with the codes of the YZF750 (4FM), FZR600 (3HE), etc.
So you can be sure the parts are exactly the same. Why would they change the partnumber, even only the first 3 digits regarding the model code, and not the part itself?

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Snod Blatter
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Re: TDM850 flywheel used in a TRX850

Post by Snod Blatter » Sun Jun 30, 2019 4:33 pm

It wouldn't surprise me if they are different weights, do you have a decent set of scales to hand?
'95 4NX with K&N filter, Motad Venom cans, YSS PD valves, Ohlins fork springs, 530 C+S, Green CDI, 11/16 radial master cylinder, +30mm jack up dog bones. Enjoyable money pit.

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